Railway cars, of the type commonly referred to as covered hopper cars, are widely used by the railroad industry to transport various products throughout the country. These hopper cars are generally trough like cars having an interior storage area and openings in the top of the hopper called hatches to allow material to be transferred into the hopper. It is the general practice in the industry to load material into the hopper car through the hatch in the roof of the hopper car and subsequently remove the material from an opening in the bottom section of the hopper.
A single car may have several hatch covers that are used to close the openings in the top of the hopper car to prevent spillage and unwanted materials and infestation to enter the hopper car during transportation and storage of the material in the hopper car. The hatch may extend the entire length of he hopper car; therefore, it is generally desirable to have multiple hatch covers due to the unwieldy nature of single hatch. The hatch covers are generally planar sections that have a seal around their perimeter and are placed over the openings in the top of the hopper car for securely sealing the hatch opening of the hopper car during transportation.
The hatch covers are usually held down by one of two methods or a combination of both. One of such methods or devices utilized to secure the hatch covers to the hopper cars are hinged covers with batten bars that extend transversely across the hatch cover and are secured to the roof of the hopper car. The batten bars are generally narrow sheets of steel, aluminum or other relatively high strength material that are hinged at one end with a hinge pin assembly and held by a latch or locking device adjacent the hatch opening on the other end. The hinge pin assembly allows the batten bar to be swung away from a position overlying the hatch cover about an axis parallel to the top surface of the hopper car to allow opening of the hatch cover. A second method or mechanism for securing the hatch cover to the hopper car eliminates the need for batten bars by providing an overlapping lip on the cover. This approach also outfits the hatch cover with a hinge pin assembly so that it to may be rotated about an axis parallel to the top of the hopper car and secured thereto by a lock or latch.
Whichever approach is used, on either side of the hatch opening into the hopper car is an area generally designated as a walkway for railroad personnel to allow the personnel to move about the top of the car. A major drawback with prior art safety hooks is that often times the hatch cover and the batten bar are hinged to open on opposite sides of the hatch opening thus obstructing both walkways on either side of the hatch opening. This creates additional work for the railroad personnel as they are required to continually traverse the hatch opening in order to unlock the batten bars and hatch covers. In addition, the continual crossing of the hatch opening by railroad personnel to get to the latches can create Potential safety problem as well.
In order to cover such a large opening with a hatch cover that is manageable by railroad personnel it is well known to use a series of hatch covers to cover a single opening. The use of a series of hatch covers however requires that each individual hatch cover be secured to the roof of the hopper car and each joint between adjacent hatch covers be secured. This has been accomplished in the past by utilizing a variety of adjacent locking devices for holding the batten bar and hatch cover hinge pins in a secure manner.
This series of locks securing the hatch cover led to another major problem with the prior art locking devices for holding the batten bar hinge and the hatch cover hinge. The hatch cover is outfitted with a seal gasket of a resilient nature, thus, when the hatch cover is in its locked position compressing the seal, the seal about the periphery of the hatch cover supplies an upward force on the hatch cover. Therefore, when a hatch hinge or a batten bar hinge was unlocked by railroad personnel, such personnel should be careful to avoid potential injury from the hatch popping open and upward due to the force from the compressed resilient seal.
A problem associated with prior locking assemblies for the hatch covers is the possibility for the hatch cover to be accidentally left unsecured. For example, if the hatch hinge or the batten bar hinge section is not locked down with the hatch cover in its closed position this can create circumstances where the hatch cover has a tendency to fly off of the hopper car after the train is moving.